Prosthetic denture correlator



Nov. 4, 1947. E. JOHNSON ET AL PROS'IHETIC DENTURE CORRELATOR Filed May 5, 1944 2 Sheets-Sheet 1 Invent om:

' Leona/d E. Johnson Mlton LaGrandeOg/e by 1/ ttorney.

Nov. 4,1947. 1.. E. JOHNSON ET AL 2,430,177

PRQSTHETIC DENTURE CORRELATOR Filed May 5. 1944 2 Sheets-Sheet 2 I Awe/Mars; Leonard ,5 Johnson M/ton LaGra/v 09/ shy W Attorney.

Patented Nov. 4, 1.947

OFFICE 7 2,430,177 'raos'rnsrio DENTURE 'ooaaELAroa LeonardE. Johnson and Milton LaGrande Oglesby, Denver, 0010.

Application May 5, 1944, Serial No. 534,290

'9 Claims. 1

This invention relatesto the art and practice of prosthetic dentistry, and more particularly to the fabrication and operative correlation of dental restorations, and has as an object to provide improved means 'foroperatively simulating the occlusal and masticatory relationships to ba redintegrated.

A further object of the invention is to provide improved means for operatively correlating prosthetic dentures with'the condition to be redintegrated throughout a full range of occlusal and masticatory registration.

A further object of the invention isto provide improved means for correlating dental restorations with reproductions of the natural condition to be redintegrated in such manner as to fully duplicate the entire range of natural occlusal and masticatory registration.

A further object of the invention is to provide improved means for mounting and adjustably holding reproductions of a natural denture in such simulation of their natural registration as will facilitate precise occlusarand masticatory correlation of adental'rest'oration therewith.

A further object of the invention is to provide improved mounting for dental casts wherehrough full simulation of the natural occlusal and masticatory registration of the original dentures may be developed.

A further object of the invention is to provide an improved mounting for dental casts operatively yieldable throughout a full spherical orbit to simulate and trace the paths of occlusal and masticatory registration natural to the original dentures.

A further object of "the invention is to provide improved means for the removable and replaceable association of dental casts in fixed relation with relatively movable supporting elements of a cast-mounting device.

A further object of the invention is to provide improved means for resiliently associating and. operatively interconnecting spaced supporting elements of a dental cast-mounting device for relative adjustment throughout the range of a full spherical orbit.

A further object of the invention is to provide an improved-dental cast-mounting device susceptible of manipulation to check, trace, lit, and polish the tooth facets of a dental restoration against and for occlusal and masticatory registration with replicas of the natural dentures to be restored.

A'iurther object of the invention is to provide an improved dental cast=mounting device that 2 is Simple an inexpensive of manufacture, convenient and e'iiicient'i'n use, rugged and durable of construction, susceptible of ready repair and rehabilitation, operable throughout a'wide range'of relative adjustments, and positive and practical in "the attainment of the ends desired.

With the "foregoing and other objects in view, our invention consists in the construction, arrangement, and operative combination of elements hereinafter set forth, pointed out in our claims, and illustrated by the accompanying drawings, in which Figure 1 is a rear end elevation of a simplified and somewhat conventionalized'embodiment of the'inv'entio'n as operatively assembled and associated'with dental'casts ready ioripra'ctical use. Figure 2 is aside elevation'of the showing of Figure -1, broken lines indicating analt'ernative relative position of 'the units constituting the device. Figure 3 is a side elevation of the units "comprised in the construction according to Figures 1 and 2 as conveniently disassembled to facilitate cast-mounting, and "the like. Figure4 is a plan view of a cast-supporting element or base comprised within the invention. Figure 5 is a cross section taken on 'the indicated line 5-5 of Figure 4. Figure 6 is across section taken on the indicated line 6-6 of Figure 4. Figure"? is a plan view of an alternative castsupporting element or base employ-able in place of the construction shown in the preceding Figures. Figure '8 is 'a cross section taken on the indicated line 88 of Figure 7. Figure 9 is a cross section taken on the indicated. line 9-9 of Figure '7. Figure 10 is a fragmentary, detail elevation of an alternative hinge joint construction 'employable as a substitute for the hinge shown in Figures 1, 2 and 3. Figure 11 is a fragmentary, detail elevation of an arrangement for removab'ly and 'replaceably interconnecting certain elements of the invention. Figure 12 is a fragmentary, detail elevation of an arrangement for removably and replaceably interconnecting certain other elements of the invention.

In the practice of prosthetic dentistry, one very important technical problem is the shaping and fitting oi the restoration occlusal surfaces to register, meet, and operatively cooperate with opposed surfaces in conformity with the estab-,

lished habits, idiosyncrasies, and tooth facet inclinations of the user. The many factors peculiar to the individual have heretofore made proper operative correlation of the restoration with the associated dental elements almost invariably a matter susceptible of satisfactory resolution only through repetitious adjustments and.

, game modifications had in the dental chair after installations of the restoration, the use of fixed, even though adjustable, mechanically simulated axes of articulation, planes and arcs of occlusion, lines, planes, and axes of symmetry, and the like, failing to provide that full orbital range necessary for reconstitution of the natural dental relationships determinable irom the traces and'indices established through use of the original dentures. To facilitate attainment of the desired operative registration between restorations and their associated dental elements, and to thereby largely obviate the necessity for adjustments and corrections in the dental chair, the instant invention provides a device for laboratory use wherein the relationships to be redintegrated can be fully and accurately portrayed and operatively duplicated as a check mounting for the restoration. 7

The improved device consists, essentially, of a pair of cast-mounting bases hingedly, yieldably, and separably associated for registration at times in spaced opposition and for relative manipulation throughout a full spherical orbit wherein every phase and condition of dental occlusive .attitude may be exemplified. In the practical use of the improved device, impressions of the natural dentures, both upper and lower, and the associated conditions requiring restoration or correction are taken and casts prepared therefrom, which casts are secured to the mounting bases of the device and positioned thereon to register in simulation of the natural relationships they portray when said bases are in spaced, substantially parallel relation at one limit of their range of relative movement as determined by the normal mechanical characteristics of the device, the thus-mounted casts duplicating the locus into which the restoration or correction is to be adapted and providing, through the novel features of the device, means for exactly correlating the restoration or correction, and particularly the facet disposition and inclination thereof, with the operative range and pattern of the original dentures.

In the embodiment of the invention illustrated by Figures 1, 2 and 3, similar, substantially rigid, U-shaped yokes l and it, formed by bending a straight'length of relatively stifi rod to provide a long, straight base terminating in shorter, spaced, parallel arms perpendicular to said base, of approximately equal size, each carry a series of apcrtured hinge bosses l1 fixedly projecting radially from the yoke base section in such spacing as will permit alignment of their apertures to receive a pin 8 engageable therethrough to separably and hingedly interconnect said yokes with their base sections in adjacent parallelism and their arms substantially coplanar, in which relationship the planes defined by said yokes are articulated for relative angular adjustment about the axis of the pin I87. One set of the hinge bosses H is preferably ofiset from the plane of the associated yoke, as shown, to so dispose the hinge axis as to permit the yokes to lie in parallel adjacency at one limit of their range of relative actuation and to swing into substantially coplanar divergence adjacent the opposite limit of such range. The rod material forming the yokes l5 and [6 may conveniently be tubular, but in any event the arms of said yokes are formed with axial, end-opening bores adapted to telescopically receive, seat, and position resiliently-yieldable links operatively connecting between the hinge formed by said yokes and the cast-mounting bases 'of the device. The links carried by the yokes l5 and [6 are functionally identical and are structurally alike in that they are formed from the same material to each include a spring coil, but they difier somewhat in arrangement and specific disposition, the pair of links carried by each yoke being themselves similar and oppositely arranged in a disposition contrasting with that of the links secured to the other yoke. The links 19 carried by the yoke !5 are formed from lengths of relatively stifi spring wire, each of which is telescoped at one end within and suitably secured to an arm of the yoke l5 from which it projects as a straight axial extension for a space and is then smoothly coiled to form a helix 20 substantially in the plane of the yoke l5 and inwardly ofthe yoke from its associated yoke arm, said helix extending through approximately one and one-quarter turns and terminating at the point of its are remote from its yoke base in an integral, straight finger 2i bent to project in substantially perpendicular relation from the plane of the yoke 15, the two said fingers 2] of the links l9 thus determining a plane perpendicular to that of said yoke and parallel with the hinge axis of the pin it. In comparable manner, suitable lengths of the stiff spring wire are telescopically seated and secured in ends of the arms of the yoke Hi, from Which they extend axially for a space, as the links 22, and are then bent at right angles inwardly toward each other and oppositely coiled through one and one-quarter turns to form helixes 23 whereof the planes are substantially perpendicular to that of the yoke l6 and on the side of said yoke opposite to that overhung by the fingers 2|, terminal portions of the link wires 22 passing beneath the initial curve of the corresponding helix and being then bent to project in spaced relation away from their helixes as straight fingers 24 defining a plane parallel with the hinge axis of the pin l 8 and perpendicular to the plane of the yoke' 16, said fingers 24 being thus disposed to approximately underlie the fingers 2! when the yokes l5 and I6 approach coplanar relation at the limit of their angular separation.

Each pair of corresponding link fingers, 2| and 24, is adapted to engage with and operatively connect a cast-mounting base through the associated links with the related yoke, and since, in a given device, said bases are preferably identical in construction and relation with the other elements of the unit, but one thereof will be described. The cast-mounting base incorporated in the device shown in Figures 1, 2 and 3 is illustrated in detail in Figures 4, 5 and 6, wherein it is shown to consist of a trapezoidal plate 25 formed with a perpendicularly-related, integral fiange 26 marginally along its greater parallel side, an inturned lip 27 marginally of its lesser parallel side in spaced opposition with the flange 25, and a length 28 of tubular material bent intermediate its 'ends to approximate V-shape and secured to and against the face of the plate 25 with its apex engaged under the lip 21, its divergent legs substantially paralleling the divergent sides of said plate, and its free ends intersecting and extending outwardly of said plate beyond the flange 26 in a spacing corresponding to that between the paired fingers 2| or 24. A cast-mounting base of the type shown and described is carried by each pair of links l9 and 22, the paired fingers 2| and 24 of said links being telescopically engaged within and secured to projecting ends of the element 28 of the associated base in such manner asto mount said bases in spaced, parallel registration with-their flanged faces in opposition when the yokes i5 and it are at the limit of their angular separation. As is clearly shown in the drawings,'each of the cast-mounting bases positions and supports one-of a pair of dental casts29 thereby so related to register in approximately normal occlusion when said bases are parallel, the said casts2i being secured to and in the desired relation with their bases by means of blocks 30 of initially plastic material, such as plaster of paris, 01:- the equivalent. The casts 29 having been initially positioned on and relative-to their bases in the desired occlusal registration, as by means'of-pillars of wax, clay, or the like, and the supporting face of the plate '25 and lip 21 having been oiled, waxed, or otherwise coated to minimize adherence of the block material thereto, said block material, in plastic state, is moulded into and in filling relation with the space between a base and its supported cast, said material, when hardened, adhering to the cast'and gripping about the legs of the element 2 8'-to firmly and rigidly loci: the base and cast together. When it is desired to remove a cast from its base, a thin blade inserted endwise between the lip 2'! and body of the block 30 functions to break the fillets of block material engaging between the plate 25 and legs of the element 23 away from the body of the block so that the latter, carrying its cast 29, can be freely lifted away from its mounting base. Figure 3 illustrates the convenience of the separable hinge, which, by withdrawal of the pin GB, permits separate handling and disposition of the mounting bases with their flanged faces directed upwardly to facilitate moulding of the blocks 30, dressing of the casts and blocks, and the like.

Alternative to the cast-mounting base construction hereinabove described, that shown in Figures 7, S and 9 may be associated with the fingers 2i and 2a in the same manner and for the same purpose set forth. The alternative base construction is developed in the form of a sub stantially oblong, relatively thick, slab unit 3| moulded or otherwise formed of suitable hard and rigid material, such as certain plastics, preferably with one rounded end. Embedded in and projecting in spaced relation from the squared end of the unit ii, a pair of tubular sleeves 32 is positioned to receive and secure the ends of the paired fingers 2! or 2%, thereby mounting the base unit in the desired relation with other,"

elements of the device, and the side and curved end margins of the unit 3! are inclined from the outer and toward the inner or mounting face of the unit. A groove 33 peripherally intersects the inclined side and curved end margins of the unit ill and is adapted to be engaged and filled by the material forming the mounting blocks 30 when the latter are moulded into enveloping relation with the unit 3| mounting face and side and curved end margins, thereby locking the finished block to and about said unit. The mounting face of .the unit 3! is intersected by a shallow recess defined by inwardlyconverging walls, wherein is closely fitted a lifter plate 34 disposed to bear against the adjacent face of a block as moulded thereover, and a threaded stud 35 is swiveled at one end in the under surface of the plate 34 for threaded engagement within and substantially through a sleeve 3'6 suitably disposed to open through the unit'portion underlying said reces's. The end of the-stud-35 remote from'the plate-34 is slotted to' receivea tool "whereby said stud may be irotated, so thatrotation of saidfstud in one direction may -operate'to firmly seat the plate 34 within its recess-and rotation of the stud in the other directionmay operate to'lift said plate out of its recess and above the adjacent surface of the unit 31, which action serves to lift'the mounting block -36 to-break away from the block body the beads engaged in'the groove 33 and free'the block for removal from the mounting base, the edge and'f'ace surfaces of the unit 3| and plate t dhavingbeen oiled or waxed prior to moulding of the block-thereover to minimize adherence of the blockmaterial thereto.

Thehinge construction developed through interconnection of' the yoke base sections by means of'the bosses Hand pin 13 hasdisadvantages in certain instances in that'it tends to obstruct and hamper interior inspection of cast relationships when in'registration, and such disadvantage may be obviated, with no change in the functional or other structural characteristics of the device, through use of a hinge construction such as is shown in Figure 10. When the alternative hinge of Figure lil is employedythestraight,.parallel base sections of the yokes i5 and it, with their bosses ll and pin l8, are omitted and the relatively shorter yoke arm sections, indicated at 31 in Figure 10, are retained in their previously-described association with the links [9 and 22. Inner, adjacent ends or the armsections are formed or'rigidly connected with like terminal bosses 33 disposed in end-contacting, axial alignment for registration of internally-threaded bores formed axially therethrough, and'& threaded stud 39 threadedly engages within and extends through said bores to hingedly and clampably interconnect the bosses 38. As will be apparent, a hinge of the'type'shown in Figure 10 will be required to connect each link 19 withits associated link22, and it is desirable that the studs 39 of the two such hinges utilized in each complete device be oppositely threaded, so that the bosses at in each joint tend to clamp together as the arm sections 55'! approach their maximum of angular separation and tend toseparate and loosen as the said armsections approach each other as an incident of cast separation.

While throughout the foregoing description the links H) and 22 and their fingers 2i and 24 have been referred to as, at least impliedly, permanently secured to their respective mounting and associated elements, his to be noted'that the telescopic reception of said link and finger ends within tubular elements, in every case, facilitates use of threaded studs 49 engaging through side walls of said, tubular elements, as indicated in Figures 11 and 12 to develop a construction wherein the resiliently-yieldable elements of the device may conveniently be removed, replaced, and adjusted, as operative needs or other occasions' may warrant.

The practical uses and advantages ofthe improved device derive quite naturally from its construction. With casts of the dentures to be restored mounted for mated registration on the bases rovided for such purpose, said casts may be relatively approached, separated, traversed,.'

protruded, retracted, inclined, and rotated through every possible condition and position of occlusal and masticatory registration by simple manipulation of the cast-mounting bases in the hands of an operator, the resiliently-yieldable 1 and for reaction during relative fingers l9 and 22 accommodating, particularly through their perpendicularly-related helixes 20 and 23, all deviation from the initial relation of the casts as may be necessary to fully manifest the'operative variations of position inherent in the natural dentures. The appropriate restoration having been fabricated, it is fitted to and mounted on the proper cast in duplication of its ultimate association with the natural dentures, whereafter the casts are closed together and manipulated, especially to trace the normal occlusal registration of the dentures as determined by the facet inclinations of the natural teeth, and the operative correlation of the restoration with the condition to be redintegrated thereby checked for correction and precise fitting. The restoration may be removed and replaced relative to its cast as often as may be required, may be marked for correction by means of tracing media engaged between the casts, may be ground and worked while in position on its cast, and may be facet-polished to precise fit through the use of proper abrasives suitably interposed between rubbing engagement of the registered casts.

While the improvement has been primarily described with reference to its use in the correlation and fitting of partial prosthetic dentures, it is evident that the device is not necessarily correspondingly limited as to utility and is adapted for advantageous employment in the fitting, conditioning and operative correlation of full prosthetic dentures.

Since many changes, variations, and modifications of the specific form, construction, and arrangement of the elements shown and described may be had without departing from the spirit of the invention, we wish to be understood as being limited solely by the scope of the appended claims, ratherthan by any details of the illustrative showing and foregoing description.

We claim as our invention:

1. A prosthetic denture correlator comprising a pair of like cast-mounting bases disposable in spaced, substantially parallel opposition, a laterally-oifset hinge intermediate and normally parallel With the planes of said bases, a pair of spaced, similar links operatively connecting each of said bases in supported relation with one of the hinge members, and a single loop, axially and circumferentially expansible and contractible helix formed in each of said links for complementary resilient cooperation efiective to vary each base attitude relative to its hinge mounting and to the other base.

2. A prosthetic denture correlato as set forth in claim 1, wherein the helixes of the paired links connecting with the same base are operatively opposed and substantially coplanar.

3. A prosthetic denture correlator as set forth in claim 1, wherein the operatively opposed helixes of the paired links connecting with one of the bases are substantially coplanar with the associated base, and the operatively opposed helixes of the paired links connecting with the other of the bases define a plane substantially perpendicular to that of the associated base.

4. A prosthetic denture correlatoras set forth in claim 1, wherein each of the paired links is formed from a length of relatively stiiT spring wire to provide straight, perpendicularly-related terminal portions interconnected through an integrally formed single loop helix,

5. A prosthetic denture correlator as set forth in claim 1, wherein each of the paired links is formed from a length of relatively stiiT spring wire to provide straight, perpendicularly-related terminal portions interconnected through an integrally formed single loop helix substantially coplanar with one of the associated terminal portions.

6. In a prosthetic denture correlator, a pair of cast-mounting bases adapted for hinged, separable, resiliently variable association in substantially parallel opposition, each of said bases comprising a plate formed with an upstanding flange along one of its margins, a lip inturned in spaced opposition with said flange, and a substantially V-shaped tubular element fixed to said plate with its apex engaged beneath said lip and its spaced ends intersecting and extending outwardly beyond said flange.

7. In a prosthetic denture correlator, a pair of cast-mounting bases adapted for hinged, separable, resiliently-variable association in substantially parallel opposition, each of said bases comprising a trapezoidal plate formed with an upstanding flange along the greater of its parallel margins, a lip along and inturned from the lesser of the plate parallel margins, and a substantially V-shaped tubular element fixed to and in approximate paralleling relation with the converging sides of said plate with its apex engaged beneath said lip and its spaced ends intersecting and extending outwardly beyond said flange.

8. In a prosthetic denture correlator, a pair of cast-mounting bases adapted for hinged, separable, resiliently-variable association in substantially parallel opposition, each of said bases comprising a rigid slab formed with a pair of embedded tubular elements projecting in spaced, substantially parallel relation through and outwardly beyond one of its ends and inclined side margins defining greater and lesser, parallel slab faces, a lifter plate recessed in said slab for adjustment between coplanar registration with an elevation above the lesser slab face, means for adjusting said lifter plate relative to said-slab, and a groove peripherally intersecting the inclined slab side margins.

9. A cast-mounting base as set forth in claim 8, wherein the means-for adjusting the lifter plate relative to the slab comprises a threaded stud swivelled at one end centrally of and perpendicularly beneath the plate, and a threaded sleeve perpendicularly and fixedly intersecting said slab for engagement by said stud.

LEONARD E. JOHNSON. MILTON LA GRANDE OGLESBY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'IENTS Certificate of Correction Patent No. 2,430,177. November 4, 1947;

LEONARD E. JOHNSON ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Column 8, line 45, claim 8, for an elevation read and elevation; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Ofiice,

Signed and sealed this 3rd day of February, A. D. 1948.

THOMAS F. MURPHY,

Assistantflommissioner of Patents. 

